Not applicable.
Not applicable.
1. Field of the Invention
The invention relates to a vehicle-mounted tow book assembly, and more particularly to a tow hook assembly for mounting to the front of a vehicle and adapted to retract into the vehicle so as to transfer minimal force to the vehicle bumper upon a frontal impact.
2. Description of Related Art
Motor vehicles, and particularly trucks, are known to have one or more tow hooks mounted to a front end thereof. These tow hooks provide a convenient attachment point for a rope, strap or cable when the truck is being towed or pulled out of a predicament, or when the truck is doing the pulling from its front end. When the towing or pulling is applied at the rear end of the truck, a trailer hitch or receiver is available for convenient attachment.
Motor vehicles, including trucks, are also required to have supplemental restraint systems, air bags, installed for occupant safety. These supplemental restraint systems are generally intended to activate at the command of a control system that detects a frontal impact of a specified severity. It is not desirable for the air bag to activate without such an impact occurring. The vehicle is also built with a front bumper system that is adapted to readily absorb, in a planned and prescribed fashion, frontal impacts of lesser severity without activating the air bag. A tow hook assembly that is rigidly mounted to a front bumper of the vehicle presents additional challenges to designing for these desirable response characteristics, as the tow hook might protrude from the face of the bumper, and thereby become the initial point of contact during an impact.
It would therefore be advantageous to provide a tow hook assembly that is a convenient anchor for exerting a high pulling force from the front of the vehicle, but that does not transfer substantial force to the front bumper of the vehicle in the event of a frontal impact.
A tow hook assembly for a motor vehicle, the motor vehicle including a mounting base for the tow hook assembly having an opening therethrough, includes a base plate and a tow hook secured to the base plate, the base plate having a central aperture for alignment with the opening and the tow hook having a shaft passing through the central aperture, wherein the tow hook is releasable from the base plate upon imposition of a front impact force.
In a further embodiment, the base plate and the tow hook each further include a pin hole, and the assembly further includes a pin frictionally inserted through the pin hole of the base plate and the pin hole of the tow hook for mounting the tow hook to the base plate.
In a further embodiment, the base plate further includes a plurality of bolt holes for receiving bolts for mounting the base plate to a motor vehicle.
In a further embodiment, the shaft includes an outwardly extending base for engaging a rearward face of the base plate.
In a further embodiment, the base plate is a two-piece construction.
In a further embodiment, the tow hook includes a cleat-type head adapted to receive a line.
In a further embodiment of a tow hook assembly for mounting to a motor vehicle, the motor vehicle includes a generally planar surface with a relief opening therethrough and the tow hook assembly is adapted to mount to the surface in alignment with the relief opening. The tow hook assembly includes a tow hook having an enlarged base end, a shaft, and a hook portion, the base end having a pin hole passing therethrough. A two-piece base plate defines a central aperture and has a front face and a rear face, the rear face being adapted to mount against the motor vehicle with the aperture aligned with the relief opening. The rear face includes a recess surrounding the central aperture adapted to receive the enlarged base end of the tow hook. A pin hole through the base plate aligns with the pin hole in the tow hook so that a pin frictionally inserted in the pin hole of the tow hook and the pin hole of the base plate secures the tow hook to the base plate. The tow hook assembly is adapted to transfer forces in tension applied to the tow hook to the vehicle when the base plate is mounted to the vehicle, and the tow hook is adapted to be released from the base plate and displaced toward the vehicle with the shaft traveling through the central aperture and the relief opening upon application of an impact force to the tow hook.